Methods: An academic, prospective, randomized and controlled clinical trial is proposed. Patients at HPSICU who have a CVC more than 48 h will be randomized in two arms (ethanol-lock or control group with conventional measurements such as anticoagulants). In the follow-up period, we will register all necessary data to evaluate the end-points of study (CBRSI rate, catheter colonization rate, hospital stay, antimicrobial consume and adverse events due to ethanol).